/**
 * Software License, Version 1.0
 * 
 * Copyright 2003 The Trustees of Indiana University.  All rights reserved.
 * 
 *
 *Redistribution and use in source and binary forms, with or without 
 *modification, are permitted provided that the following conditions are met:
 *
 *1) All redistributions of source code must retain the above copyright notice,
 * the list of authors in the original source code, this list of conditions and
 * the disclaimer listed in this license;
 *2) All redistributions in binary form must reproduce the above copyright 
 * notice, this list of conditions and the disclaimer listed in this license in
 * the documentation and/or other materials provided with the distribution;
 *3) Any documentation included with all redistributions must include the 
 * following acknowledgement:
 *
 *"This product includes software developed by the Community Grids Lab. For 
 * further information contact the Community Grids Lab at 
 * http://communitygrids.iu.edu/."
 *
 * Alternatively, this acknowledgement may appear in the software itself, and 
 * wherever such third-party acknowledgments normally appear.
 * 
 *4) The name Indiana University or Community Grids Lab or NaradaBrokering, 
 * shall not be used to endorse or promote products derived from this software 
 * without prior written permission from Indiana University.  For written 
 * permission, please contact the Advanced Research and Technology Institute 
 * ("ARTI") at 351 West 10th Street, Indianapolis, Indiana 46202.
 *5) Products derived from this software may not be called NaradaBrokering, 
 * nor may Indiana University or Community Grids Lab or NaradaBrokering appear
 * in their name, without prior written permission of ARTI.
 * 
 *
 * Indiana University provides no reassurances that the source code provided 
 * does not infringe the patent or any other intellectual property rights of 
 * any other entity.  Indiana University disclaims any liability to any 
 * recipient for claims brought by any other entity based on infringement of 
 * intellectual property rights or otherwise.  
 *
 *LICENSEE UNDERSTANDS THAT SOFTWARE IS PROVIDED "AS IS" FOR WHICH NO 
 *WARRANTIES AS TO CAPABILITIES OR ACCURACY ARE MADE. INDIANA UNIVERSITY GIVES
 *NO WARRANTIES AND MAKES NO REPRESENTATION THAT SOFTWARE IS FREE OF 
 *INFRINGEMENT OF THIRD PARTY PATENT, COPYRIGHT, OR OTHER PROPRIETARY RIGHTS. 
 *INDIANA UNIVERSITY MAKES NO WARRANTIES THAT SOFTWARE IS FREE FROM "BUGS", 
 *"VIRUSES", "TROJAN HORSES", "TRAP DOORS", "WORMS", OR OTHER HARMFUL CODE.  
 *LICENSEE ASSUMES THE ENTIRE RISK AS TO THE PERFORMANCE OF SOFTWARE AND/OR 
 *ASSOCIATED MATERIALS, AND TO THE PERFORMANCE AND VALIDITY OF INFORMATION 
 *GENERATED USING SOFTWARE.
 */
package cgl.narada.service.storage;

import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.DataInputStream;
import java.io.DataOutputStream;
import java.io.IOException;

/** Provides information regarding a sequence number and the destinations
 associated with this sequence number 

 @author Shrideep Pallickara
 $Date$
 $Revision$
 */

public class SequenceDestinations {

  private long    sequenceNumber;

  private int[]   destinations;

  private boolean hasDestinations   = true;
  private int     numOfDestinations = 0;

  private String  moduleName        = "SequenceDestinations: ";

  public SequenceDestinations(long sequenceNumber, int[] destinations) {
    this.sequenceNumber = sequenceNumber;
    this.destinations = destinations;
    if (destinations == null) {
      hasDestinations = false;
      return;
    }

    if (destinations.length == 0) {
      hasDestinations = false;
    }

    numOfDestinations = destinations.length;
  }

  public long getSequenceNumber() {
    return sequenceNumber;
  }

  public boolean hasDestinations() {
    return hasDestinations;
  }

  public int[] getDestinations() {
    return destinations;
  }

  /** Checks to see if t he destinations list contains the specified
   entity id */
  public boolean containsDestination(int entityId) {

    if (!hasDestinations) {
      return false;
    }

    for (int i = 0; i < numOfDestinations; i++) {
      if (destinations[i] == entityId) {
        return true;
      }
    }/*end for */

    return false;
  }

  /** If all the destinations have been set to zero, there aren't any valid
   destinations anymore */
  public boolean hasValidDestinations() {
    if (!hasDestinations) {
      return false;
    }

    for (int i = 0; i < numOfDestinations; i++) {
      if (destinations[i] != 0) {
        return true;
      }
    }/*end for */

    return false;
  }

  /** Removes a destination from the set of valid destinations */
  public void removeDestination(int entityId) {

    for (int i = 0; i < numOfDestinations; i++) {
      if (destinations[i] == entityId) {
        destinations[i] = 0;
        return;
      }
    }/*end for */
  }

  public SequenceDestinations(byte[] marshalledBytes) {
    ByteArrayInputStream baInputStream = new ByteArrayInputStream(
        marshalledBytes);
    DataInputStream din = new DataInputStream(baInputStream);

    try {
      sequenceNumber = din.readLong();

      numOfDestinations = din.readInt();

      if (numOfDestinations == 0) {
        hasDestinations = false;
      }

      if (numOfDestinations != 0) {
        destinations = new int[numOfDestinations];
        for (int i = 0; i < numOfDestinations; i++) {
          destinations[i] = din.readInt();
        }
      }

    } catch (IOException ioe) {
      System.out.println(moduleName + "Error while un-marshalling");
    }
    /** end try-catch block*/

  }

  public byte[] getBytes() {
    ByteArrayOutputStream baOutputStream = new ByteArrayOutputStream();
    DataOutputStream dout = new DataOutputStream(baOutputStream);
    byte[] marshalledBytes = null;
    try {
      dout.writeLong(sequenceNumber);

      if (hasDestinations) {
        numOfDestinations = destinations.length;
      }

      dout.writeInt(numOfDestinations);

      if (numOfDestinations != 0) {
        for (int i = 0; i < numOfDestinations; i++) {
          dout.writeInt(destinations[i]);
        }
      }

      marshalledBytes = baOutputStream.toByteArray();
    } catch (IOException ioe) {
      System.out.println(moduleName + "Error while marshalling");
    }
    /** end try-catch block*/

    return marshalledBytes;
  }

}